In the blow molding of hollow plastic articles, it has been common to close a hot tube within a mold and blow a hollow container with an integral handle. Where the tube comprises a single layer of plastic, this is readily achieved by pinching off the plastic in the area that forms the hollow of the handle. However, where a multi-layer plastic is desired, as, for example, where there is an intermediate plastic layer required for providing properties such as permeability or other properties as, for example, are required for containing solvent based products, it has been found that in order to weld the pinch off areas, a large and unsightly pinch off must be provided which not only is unsightly but forms a seam line that makes the handle uncomfortable to hold. In addition, this construction weakens the drop test performance of the container.
Accordingly, among the objectives of the present invention are to provide a method and apparatus for forming multi-layer containers having an integral handle which provide for proper pinch off; which avoid large uncomfortable and unsightly pinch offs; which have adequate drop test performance; and which minimize the number of handling steps in the formation of the bottle.
In accordance with the invention the method and apparatus for making a multi-layer plastic bottle with a handle for holding liquids and the like comprises enclosing a hollow parison of molten plastic which is at a blow molding temperature, pinching a portion of the hollow parison as the mold closes to form a hollow moil portion, simultaneously pinching a portion of the hollow parison to form a hollow handle portion while leaving a portion of the parison to provide a passage from the moil portion to the handle portion and thereafter expanding the parison through the moil portion to form the container.